Attorney General Eric Holder said Wednesday that just because states are legalizing marijuana for recreational purposes doesn’t mean minors will be able to roll up a joint.

“People cannot buy alcohol I guess now until you’re age… age 21, but young people find ways to get alcohol because adults can have access to it,” Holder said before the Senate Judiciary Committee. “I’m not sure that we will see the same thing here given what we have said with regard to our enforcement priorities.”

His comments came as Colorado and Washington state have been implementing new laws allowing recreational pot. Marijuana remains illegal under federal law, and under questioning, Holder defended the Obama administration’s stance in allowing the states to move forward with their laws while the feds work to make sure the drug doesn’t become available to minors or move across state lines.

“The distribution of marijuana to minors will… will entail a very vigorous federal response,” Holder said.

Alabama Republican Sen. Jeff Sessions, a member of the committee, lamented President Barack Obama’s recent comments that marijuana isn’t more harmful than alcohol, saying he was “heartbroken” to hear Obama argue that states’ experiments in legalization should go forward. Sessions said the country had previously worked to“create a hostility to drug use” that shouldn’t recede.

“I think that the use of any drug is potentially harmful,” Holder said of Obama’s comments. “And included in that would be alcohol.”

Sessions was skeptical. “Well, Lady Gaga says she’s addicted to it and it’s not harmless,” he said.